CV-1 and MRC-5 mixed cells for simultaneous detection of herpes simplex viruses and varicella zoster virus in skin lesions.

Abstract

Culture for varicella zoster virus (VZV) is relatively insensitive. Herpes simplex viruses (HSV) culture methods, which rely on primary rabbit kidney (pRK), mink lung (Mv1Lu) or the ELVIS HSV culture system fail to detect VZV. Culture of atypical vesicular skin lesions should be able to detect both HSV and VZV. In this study, we evaluated the sensitivity of a newly developed mixture of CV-1/MRC-5 cells for the concurrent detection of both HSV and VZV. The CV-1/MRC-5 mixed cells were compared with pRK cells and Mv1Lu cells for the detection of HSV and to MRC-5 and A-549 cells for the detection of VZV. Fresh clinical samples submitted for HSV culture, VZV culture, and/or direct immunofluorescent assay (DFA) as well as frozen clinical samples previously positive for VZV were used for these comparisons. This preliminary study suggest that CV-1/MRC-5 mixed cells are as sensitive as pRK and Mv1Lu cells for the detection of HSV and appear to be more sensitive than MRC-5 and A-549 cells for the detection of VZV. Although the sample size is small, pre-CPE staining with VZV specific monoclonal antibody (Mab) at day 2 post-inoculation may provide a rapid detection of VZV with these mixed cells, but not with MRC-5 or A549 cells. In addition, culture of VZV in mixed cells from fresh clinical specimens appears to be as sensitive as antigen detection by DFA. Finally, 1% of specimens from skin lesions submitted for HSV culture grew VZV, highlighting the importance of culturing for both VZV and HSV, particularly in the case of atypical lesions. CV-1/MRC-5 mixed cells are highly sensitive for the simultaneous culture of HSV and VZV. The ability to detect either HSV or VZV from skin lesions is important for patient management.